| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S Y S T E M . O S _ L I B -- |
| -- -- |
| -- S p e c -- |
| -- -- |
| -- Copyright (C) 1995-2022, Free Software Foundation, Inc. -- |
| -- -- |
| -- GNAT is free software; you can redistribute it and/or modify it under -- |
| -- terms of the GNU General Public License as published by the Free Soft- -- |
| -- ware Foundation; either version 3, or (at your option) any later ver- -- |
| -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- |
| -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- |
| -- or FITNESS FOR A PARTICULAR PURPOSE. -- |
| -- -- |
| -- As a special exception under Section 7 of GPL version 3, you are granted -- |
| -- additional permissions described in the GCC Runtime Library Exception, -- |
| -- version 3.1, as published by the Free Software Foundation. -- |
| -- -- |
| -- You should have received a copy of the GNU General Public License and -- |
| -- a copy of the GCC Runtime Library Exception along with this program; -- |
| -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- |
| -- <http://www.gnu.org/licenses/>. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- Operating system interface facilities |
| |
| -- This package contains types and procedures for interfacing to the |
| -- underlying OS. It is used by the GNAT compiler and by tools associated |
| -- with the GNAT compiler, and therefore works for the various operating |
| -- systems to which GNAT has been ported. This package will undoubtedly grow |
| -- as new services are needed by various tools. |
| |
| -- This package tends to use fairly low-level Ada in order to not bring in |
| -- large portions of the RTL. For example, functions return access to string |
| -- as part of avoiding functions returning unconstrained types. |
| |
| -- Except where specifically noted, these routines are portable across all |
| -- GNAT implementations on all supported operating systems. |
| |
| -- Note: this package is in the System hierarchy so that it can be directly |
| -- be used by other predefined packages. User access to this package is via |
| -- a renaming of this package in GNAT.OS_Lib (file g-os_lib.ads). |
| |
| with System.Strings; |
| |
| package System.OS_Lib is |
| pragma Preelaborate; |
| |
| ----------------------- |
| -- String Operations -- |
| ----------------------- |
| |
| -- These are reexported from package Strings (which was introduced to |
| -- avoid different packages declaring different types unnecessarily). |
| -- See package System.Strings for details. |
| |
| subtype String_Access is Strings.String_Access; |
| |
| function "=" (Left : String_Access; Right : String_Access) return Boolean |
| renames Strings."="; |
| |
| procedure Free (X : in out String_Access) renames Strings.Free; |
| |
| subtype String_List is Strings.String_List; |
| |
| function "=" (Left : String_List; Right : String_List) return Boolean |
| renames Strings."="; |
| |
| function "&" (Left : String_Access; Right : String_Access) |
| return String_List renames Strings."&"; |
| function "&" (Left : String_Access; Right : String_List) |
| return String_List renames Strings."&"; |
| function "&" (Left : String_List; Right : String_Access) |
| return String_List renames Strings."&"; |
| function "&" (Left : String_List; Right : String_List) |
| return String_List renames Strings."&"; |
| |
| subtype String_List_Access is Strings.String_List_Access; |
| |
| function "=" |
| (Left : String_List_Access; |
| Right : String_List_Access) return Boolean renames Strings."="; |
| |
| procedure Free (Arg : in out String_List_Access) renames Strings.Free; |
| |
| --------------------- |
| -- Time/Date Stuff -- |
| --------------------- |
| |
| type OS_Time is private; |
| -- The OS's notion of time is represented by the private type OS_Time. This |
| -- is the type returned by the File_Time_Stamp functions to obtain the time |
| -- stamp of a specified file. Functions and a procedure (modeled after the |
| -- similar subprograms in package Calendar) are provided for extracting |
| -- information from a value of this type. Although these are called GM, the |
| -- intention in the case of time stamps is not that they provide GMT times |
| -- in all cases but rather the actual (time-zone independent) time stamp of |
| -- the file (of course in Unix systems, this *is* in GMT form). |
| |
| Invalid_Time : constant OS_Time; |
| -- A special unique value used to flag an invalid time stamp value |
| |
| function "<" (X : OS_Time; Y : OS_Time) return Boolean; |
| function ">" (X : OS_Time; Y : OS_Time) return Boolean; |
| function ">=" (X : OS_Time; Y : OS_Time) return Boolean; |
| function "<=" (X : OS_Time; Y : OS_Time) return Boolean; |
| -- Basic comparison operators on OS_Time with obvious meanings. Note that |
| -- these have Intrinsic convention, so for example it is not permissible |
| -- to create accesses to any of these functions. |
| |
| subtype Year_Type is Integer range 1900 .. 2099; |
| subtype Month_Type is Integer range 1 .. 12; |
| subtype Day_Type is Integer range 1 .. 31; |
| subtype Hour_Type is Integer range 0 .. 23; |
| subtype Minute_Type is Integer range 0 .. 59; |
| subtype Second_Type is Integer range 0 .. 59; |
| -- Declarations similar to those in Calendar, breaking down the time |
| |
| function Current_Time return OS_Time; |
| -- Return the system clock value as OS_Time |
| |
| function Current_Time_String return String; |
| -- Returns current local time in the form YYYY-MM-DD HH:MM:SS. The result |
| -- has bounds 1 .. 19. |
| |
| function GM_Year (Date : OS_Time) return Year_Type; |
| function GM_Month (Date : OS_Time) return Month_Type; |
| function GM_Day (Date : OS_Time) return Day_Type; |
| function GM_Hour (Date : OS_Time) return Hour_Type; |
| function GM_Minute (Date : OS_Time) return Minute_Type; |
| function GM_Second (Date : OS_Time) return Second_Type; |
| -- Functions to extract information from OS_Time value in GMT form |
| |
| procedure GM_Split |
| (Date : OS_Time; |
| Year : out Year_Type; |
| Month : out Month_Type; |
| Day : out Day_Type; |
| Hour : out Hour_Type; |
| Minute : out Minute_Type; |
| Second : out Second_Type); |
| -- Analogous to the Split routine in Ada.Calendar, takes an OS_Time and |
| -- provides a representation of it as a set of component parts, to be |
| -- interpreted as a date point in UTC. |
| |
| function GM_Time_Of |
| (Year : Year_Type; |
| Month : Month_Type; |
| Day : Day_Type; |
| Hour : Hour_Type; |
| Minute : Minute_Type; |
| Second : Second_Type) return OS_Time; |
| -- Analogous to the Time_Of routine in Ada.Calendar, takes a set of time |
| -- component parts to be interpreted in the local time zone, and returns |
| -- an OS_Time. Returns Invalid_Time if the creation fails. |
| |
| ------------------ |
| -- Time_t Stuff -- |
| ------------------ |
| |
| -- Note: Do not use time_t in the compiler and host-based tools; instead |
| -- use OS_Time. |
| |
| subtype time_t is Long_Long_Integer; |
| -- C time_t can be either long or long long, so we choose the Ada |
| -- equivalent of the latter because eventually that will be the |
| -- type used out of necessity. This may affect some user code on 32-bit |
| -- targets that have not yet migrated to the Posix 2008 standard, |
| -- particularly pre version 5 32-bit Linux. Do not change this |
| -- declaration without coordinating it with conversions in Ada.Calendar. |
| |
| function To_C (Time : OS_Time) return time_t; |
| -- Convert OS_Time to C time_t type |
| |
| function To_Ada (Time : time_t) return OS_Time; |
| -- Convert C time_t type to OS_Time |
| |
| ---------------- |
| -- File Stuff -- |
| ---------------- |
| |
| -- These routines give access to the open/creat/close/read/write level of |
| -- I/O routines in the typical C library (these functions are not part of |
| -- the ANSI C standard, but are typically available in all systems). See |
| -- also package Interfaces.C_Streams for access to the stream level |
| -- routines. |
| |
| -- Note on file names. If a file name is passed as type String in any of |
| -- the following specifications, then the name is a normal Ada string and |
| -- need not be NUL-terminated. However, a trailing NUL character is |
| -- permitted, and will be ignored (more accurately, the NUL and any |
| -- characters that follow it will be ignored). |
| |
| type File_Descriptor is new Integer; |
| -- Corresponds to the int file handle values used in the C routines |
| |
| Standin : constant File_Descriptor := 0; |
| Standout : constant File_Descriptor := 1; |
| Standerr : constant File_Descriptor := 2; |
| -- File descriptors for standard input output files |
| |
| Invalid_FD : constant File_Descriptor := -1; |
| -- File descriptor returned when error in opening/creating file |
| |
| Null_FD : constant File_Descriptor := -2; |
| -- Uninitialized file descriptor |
| |
| procedure Close (FD : File_Descriptor; Status : out Boolean); |
| -- Close file referenced by FD. Status is False if the underlying service |
| -- failed. Reasons for failure include: disk full, disk quotas exceeded |
| -- and invalid file descriptor (the file may have been closed twice). |
| |
| procedure Close (FD : File_Descriptor); |
| -- Close file referenced by FD. This form is used when the caller wants to |
| -- ignore any possible error (see above for error cases). |
| |
| type Copy_Mode is |
| (Copy, |
| -- Copy the file. It is an error if the target file already exists. The |
| -- time stamps and other file attributes are preserved in the copy. |
| |
| Overwrite, |
| -- If the target file exists, the file is replaced otherwise the file |
| -- is just copied. The time stamps and other file attributes are |
| -- preserved in the copy. |
| |
| Append); |
| -- If the target file exists, the contents of the source file is |
| -- appended at the end. Otherwise the source file is just copied. The |
| -- time stamps and other file attributes are preserved if the |
| -- destination file does not exist. |
| |
| type Attribute is |
| (Time_Stamps, |
| -- Copy time stamps from source file to target file. All other |
| -- attributes are set to normal default values for file creation. |
| |
| Full, |
| -- All attributes are copied from the source file to the target file. |
| -- This includes the timestamps, and for example also includes |
| -- read/write/execute attributes in Unix systems. |
| |
| None); |
| -- No attributes are copied. All attributes including the time stamp |
| -- values are set to normal default values for file creation. |
| |
| -- Note: The default is Time_Stamps, which corresponds to the normal |
| -- default on Windows style systems. Full corresponds to the typical |
| -- effect of "cp -p" on Unix systems, and None corresponds to the typical |
| -- effect of "cp" on Unix systems. |
| |
| -- Note: Time_Stamps and Full are not supported on VxWorks 5 |
| |
| procedure Copy_File |
| (Name : String; |
| Pathname : String; |
| Success : out Boolean; |
| Mode : Copy_Mode := Copy; |
| Preserve : Attribute := Time_Stamps); |
| -- Copy a file. Name must designate a single file (no wildcards allowed). |
| -- Pathname can be a filename or directory name. In the latter case Name |
| -- is copied into the directory preserving the same file name. Mode |
| -- defines the kind of copy, see above with the default being a normal |
| -- copy in which the target file must not already exist. Success is set to |
| -- True or False indicating if the copy is successful (depending on the |
| -- specified Mode). |
| |
| procedure Copy_File_Attributes |
| (From : String; |
| To : String; |
| Success : out Boolean; |
| Copy_Timestamp : Boolean := True; |
| Copy_Permissions : Boolean := True); |
| -- Copy some of the file attributes from one file to another. Both files |
| -- must exist, or Success is set to False. |
| |
| procedure Copy_Time_Stamps |
| (Source : String; |
| Dest : String; |
| Success : out Boolean); |
| -- Copy Source file time stamps (last modification and last access time |
| -- stamps) to Dest file. Source and Dest must be valid filenames, |
| -- furthermore Dest must be writable. Success will be set to True if the |
| -- operation was successful and False otherwise. |
| -- |
| -- Note: this procedure is not supported on VxWorks 5. On this platform, |
| -- Success is always set to False. |
| |
| type Mode is (Binary, Text); |
| for Mode'Size use Integer'Size; |
| for Mode use (Binary => 0, Text => 1); |
| -- Used in all the Open and Create calls to specify if the file is to be |
| -- opened in binary mode or text mode. In systems like Unix, this has no |
| -- effect, but in systems capable of text mode translation, the use of |
| -- Text as the mode parameter causes the system to do CR/LF translation |
| -- and also to recognize the DOS end of file character on input. The use |
| -- of Text where appropriate allows programs to take a portable Unix view |
| -- of DOS-format files and process them appropriately. |
| |
| function Create_File |
| (Name : String; |
| Fmode : Mode) return File_Descriptor; |
| -- Creates new file with given name for writing, returning file descriptor |
| -- for subsequent use in Write calls. If the file already exists, it is |
| -- overwritten. File descriptor returned is Invalid_FD if file cannot be |
| -- successfully created. |
| |
| function Create_New_File |
| (Name : String; |
| Fmode : Mode) return File_Descriptor; |
| -- Create new file with given name for writing, returning file descriptor |
| -- for subsequent use in Write calls. This differs from Create_File in |
| -- that it fails if the file already exists. File descriptor returned is |
| -- Invalid_FD if the file exists or cannot be created. |
| |
| function Create_Output_Text_File (Name : String) return File_Descriptor; |
| -- Creates new text file with given name suitable to redirect standard |
| -- output, returning file descriptor. File descriptor returned is |
| -- Invalid_FD if file cannot be successfully created. |
| |
| Temp_File_Len : constant Integer := 12; |
| -- Length of name returned by Create_Temp_File call (GNAT-XXXXXX & NUL) |
| |
| subtype Temp_File_Name is String (1 .. Temp_File_Len); |
| -- String subtype set by Create_Temp_File |
| |
| procedure Create_Temp_File |
| (FD : out File_Descriptor; |
| Name : out Temp_File_Name); |
| -- Create and open for writing a temporary file in the current working |
| -- directory. The name of the file and the File Descriptor are returned. |
| -- The File Descriptor returned is Invalid_FD in the case of failure. No |
| -- mode parameter is provided. Since this is a temporary file, there is no |
| -- point in doing text translation on it. |
| -- |
| -- On some operating systems, the maximum number of temp files that can be |
| -- created with this procedure may be limited. When the maximum is reached, |
| -- this procedure returns Invalid_FD. On some operating systems, there may |
| -- be a race condition between processes trying to create temp files at the |
| -- same time in the same directory using this procedure. |
| |
| procedure Create_Temp_File |
| (FD : out File_Descriptor; |
| Name : out String_Access); |
| -- Create and open for writing a temporary file in the current working |
| -- directory. The name of the file and the File Descriptor are returned. |
| -- It is the responsibility of the caller to deallocate the access value |
| -- returned in Name. |
| -- |
| -- The file is opened in binary mode (no text translation). |
| -- |
| -- This procedure will always succeed if the current working directory is |
| -- writable. If the current working directory is not writable, then |
| -- Invalid_FD is returned for the file descriptor and null for the Name. |
| -- There is no race condition problem between processes trying to create |
| -- temp files at the same time in the same directory. |
| |
| procedure Create_Temp_Output_File |
| (FD : out File_Descriptor; |
| Name : out String_Access); |
| -- Create and open for writing a temporary file in the current working |
| -- directory suitable to redirect standard output. The name of the file and |
| -- the File Descriptor are returned. It is the responsibility of the caller |
| -- to deallocate the access value returned in Name. |
| -- |
| -- The file is opened in text mode |
| -- |
| -- This procedure will always succeed if the current working directory is |
| -- writable. If the current working directory is not writable, then |
| -- Invalid_FD is returned for the file descriptor and null for the Name. |
| -- There is no race condition problem between processes trying to create |
| -- temp files at the same time in the same directory. |
| |
| procedure Delete_File (Name : String; Success : out Boolean); |
| -- Deletes file. Success is set True or False indicating if the delete is |
| -- successful. |
| |
| function File_Length (FD : File_Descriptor) return Long_Integer; |
| pragma Import (C, File_Length, "__gnat_file_length_long"); |
| |
| type Large_File_Size is range -2**63 .. 2**63 - 1; |
| -- Maximum supported size for a file (8 exabytes = 8 million terabytes, |
| -- should be enough to accommodate all possible needs for quite a while). |
| |
| function File_Length64 (FD : File_Descriptor) return Large_File_Size; |
| pragma Import (C, File_Length64, "__gnat_file_length"); |
| -- Get length of file from file descriptor FD |
| |
| function File_Time_Stamp (Name : String) return OS_Time; |
| -- Given the name of a file or directory, Name, obtains and returns the |
| -- time stamp. This function can be used for an unopened file. Returns |
| -- Invalid_Time if Name doesn't correspond to an existing file. |
| |
| function File_Time_Stamp (FD : File_Descriptor) return OS_Time; |
| -- Get time stamp of file from file descriptor FD Returns Invalid_Time is |
| -- FD doesn't correspond to an existing file. |
| |
| function Get_Debuggable_Suffix return String_Access; |
| -- Return the debuggable suffix convention. Usually this is the same as |
| -- the convention for Get_Executable_Suffix. The result is allocated on |
| -- the heap and should be freed after use to avoid storage leaks. |
| |
| function Get_Executable_Suffix return String_Access; |
| -- Return the executable suffix convention. The result is allocated on the |
| -- heap and should be freed after use to avoid storage leaks. |
| |
| function Get_Object_Suffix return String_Access; |
| -- Return the object suffix convention. The result is allocated on the heap |
| -- and should be freed after use to avoid storage leaks. |
| |
| function Get_Target_Debuggable_Suffix return String_Access; |
| -- Return the target debuggable suffix convention. Usually this is the same |
| -- as the convention for Get_Executable_Suffix. The result is allocated on |
| -- the heap and should be freed after use to avoid storage leaks. |
| |
| function Get_Target_Executable_Suffix return String_Access; |
| -- Return the target executable suffix convention. The result is allocated |
| -- on the heap and should be freed after use to avoid storage leaks. |
| |
| function Get_Target_Object_Suffix return String_Access; |
| -- Return the target object suffix convention. The result is allocated on |
| -- the heap and should be freed after use to avoid storage leaks. |
| |
| function Is_Absolute_Path (Name : String) return Boolean; |
| -- Returns True if Name is an absolute path name, i.e. it designates a |
| -- file or directory absolutely rather than relative to another directory. |
| |
| function Is_Directory (Name : String) return Boolean; |
| -- Determines if the given string, Name, is the name of a directory. |
| -- Returns True if so, False otherwise. Name may be an absolute path |
| -- name or a relative path name, including a simple file name. If it is |
| -- a relative path name, it is relative to the current working directory. |
| |
| function Is_Executable_File (Name : String) return Boolean; |
| -- Determines if the given string, Name, is the name of an existing file |
| -- that is executable. Returns True if so, False otherwise. Note that this |
| -- function simply interrogates the file attributes (e.g. using the C |
| -- function stat), so it does not indicate a situation in which a file may |
| -- not actually be readable due to some other process having exclusive |
| -- access. |
| |
| function Is_Owner_Readable_File (Name : String) return Boolean; |
| -- Determines if the given string, Name, is the name of an existing file |
| -- that is readable. Returns True if so, False otherwise. Note that this |
| -- function simply interrogates the file attributes (e.g. using the C |
| -- function stat), so it does not indicate a situation in which a file may |
| -- not actually be readable due to some other process having exclusive |
| -- access. |
| |
| function Is_Regular_File (Name : String) return Boolean; |
| -- Determines if the given string, Name, is the name of an existing |
| -- regular file. Returns True if so, False otherwise. Name may be an |
| -- absolute path name or a relative path name, including a simple file |
| -- name. If it is a relative path name, it is relative to the current |
| -- working directory. |
| |
| function Is_Symbolic_Link (Name : String) return Boolean; |
| -- Determines if the given string, Name, is the path of a symbolic link on |
| -- systems that support it. Returns True if so, False if the path is not a |
| -- symbolic link or if the system does not support symbolic links. |
| -- |
| -- A symbolic link is an indirect pointer to a file; its directory entry |
| -- contains the name of the file to which it is linked. Symbolic links may |
| -- span file systems and may refer to directories. |
| |
| function Is_Owner_Writable_File (Name : String) return Boolean; |
| -- Determines if the given string, Name, is the name of an existing file |
| -- that is writable. Returns True if so, False otherwise. Note that this |
| -- function simply interrogates the file attributes (e.g. using the C |
| -- function stat), so it does not indicate a situation in which a file may |
| -- not actually be writable due to some other process having exclusive |
| -- access. |
| |
| function Is_Read_Accessible_File (Name : String) return Boolean; |
| -- Determines if the given string, Name, is the name of an existing file |
| -- that is readable. Returns True if so, False otherwise. |
| |
| function Is_Write_Accessible_File (Name : String) return Boolean; |
| -- Determines if the given string, Name, is the name of an existing file |
| -- that is writable. Returns True if so, False otherwise. |
| |
| function Is_Readable_File (Name : String) return Boolean |
| renames Is_Read_Accessible_File; |
| function Is_Writable_File (Name : String) return Boolean |
| renames Is_Write_Accessible_File; |
| -- These subprograms provided for backward compatibility and should not be |
| -- used. Use Is_Owner_Readable_File/Is_Owner_Writable_File or |
| -- Is_Read_Accessible_File/Is_Write_Accessible_File instead. |
| |
| function Locate_Exec_On_Path (Exec_Name : String) return String_Access; |
| -- Try to locate an executable whose name is given by Exec_Name in the |
| -- directories listed in the environment Path. If the Exec_Name does not |
| -- have the executable suffix, it will be appended before the search. |
| -- Otherwise works like Locate_Regular_File below. If the executable is |
| -- not found, null is returned. |
| -- |
| -- Note that this function allocates memory for the returned value. This |
| -- memory needs to be deallocated after use. |
| |
| function Locate_Regular_File |
| (File_Name : String; |
| Path : String) return String_Access; |
| -- Try to locate a regular file whose name is given by File_Name in the |
| -- directories listed in Path. If a file is found, its full pathname is |
| -- returned; otherwise, a null pointer is returned. If the File_Name given |
| -- is an absolute pathname, then Locate_Regular_File just checks that the |
| -- file exists and is a regular file. Otherwise, if the File_Name given |
| -- includes directory information, Locate_Regular_File first checks if the |
| -- file exists relative to the current directory. If it does not, or if |
| -- the File_Name given is a simple file name, the Path argument is parsed |
| -- according to OS conventions, and for each directory in the Path a check |
| -- is made if File_Name is a relative pathname of a regular file from that |
| -- directory. |
| -- |
| -- Note that this function allocates some memory for the returned value. |
| -- This memory needs to be deallocated after use. |
| |
| Seek_Cur : constant := 1; |
| Seek_End : constant := 2; |
| Seek_Set : constant := 0; |
| -- Used to indicate origin for Lseek call |
| |
| procedure Lseek |
| (FD : File_Descriptor; |
| offset : Long_Integer; |
| origin : Integer); |
| pragma Import (C, Lseek, "__gnat_lseek"); |
| -- Sets the current file pointer to the indicated offset value, relative |
| -- to the current position (origin = SEEK_CUR), end of file (origin = |
| -- SEEK_END), or start of file (origin = SEEK_SET). |
| |
| function Normalize_Pathname |
| (Name : String; |
| Directory : String := ""; |
| Resolve_Links : Boolean := True; |
| Case_Sensitive : Boolean := True) return String; |
| -- Returns a file name as an absolute path name, resolving all relative |
| -- directories, and symbolic links. If Name is a relative path, it is |
| -- interpreted relative to Directory, or to the current directory if |
| -- Directory is the empty string (the default). The result returned is |
| -- the normalized name of the file, containing no "." or ".." components, |
| -- and no duplicated directory separators. For most cases, if two file |
| -- names designate the same file through different paths, |
| -- Normalize_Pathname will return the same canonical name in both cases. |
| -- However, there are cases when this is not true; for example, this is |
| -- not true in Unix for two hard links designating the same file. |
| -- |
| -- On Windows, the returned path will start with a drive letter. If |
| -- Directory is empty (the default) and Name is a relative path or an |
| -- absolute path without drive letter, the letter of the current drive |
| -- will start the returned path. If Case_Sensitive is True (the default), |
| -- then this drive letter will be forced to upper case ("C:\..."). |
| -- |
| -- If Resolve_Links is set to True, then the symbolic links, on systems |
| -- that support them, will be fully converted to the name of the file or |
| -- directory pointed to. This is slightly less efficient, since it |
| -- requires system calls. |
| -- |
| -- If Name is empty or the path contains symbolic links that can't be |
| -- resolved (for example there is a symbolic link circularity, |
| -- e.g. A is a symbolic link for B, and B is a symbolic link for A), then |
| -- Normalize_Pathname returns an empty string. |
| -- |
| -- For case-sensitive file systems, the value of Case_Sensitive parameter |
| -- is ignored. For file systems that are not case-sensitive, such as |
| -- Windows, if this parameter is set to False, then the file and directory |
| -- names are folded to lower case. This allows checking whether two files |
| -- are the same by applying this function to their names and comparing the |
| -- results. If Case_Sensitive is set to True, this function does not change |
| -- the casing of file and directory names. |
| |
| function Open_Append |
| (Name : String; |
| Fmode : Mode) return File_Descriptor; |
| -- Opens file Name for appending, returning its file descriptor. File |
| -- descriptor returned is Invalid_FD if the file cannot be successfully |
| -- opened. |
| |
| function Open_Read |
| (Name : String; |
| Fmode : Mode) return File_Descriptor; |
| -- Open file Name for reading, returning its file descriptor. File |
| -- descriptor returned is Invalid_FD if the file cannot be opened. |
| |
| function Open_Read_Write |
| (Name : String; |
| Fmode : Mode) return File_Descriptor; |
| -- Open file Name for both reading and writing, returning its file |
| -- descriptor. File descriptor returned is Invalid_FD if the file |
| -- cannot be opened. |
| |
| function Read |
| (FD : File_Descriptor; |
| A : System.Address; |
| N : Integer) return Integer; |
| -- Read N bytes to address A from file referenced by FD. Returned value is |
| -- count of bytes actually read, which can be less than N at EOF. |
| |
| procedure Rename_File |
| (Old_Name : String; |
| New_Name : String; |
| Success : out Boolean); |
| -- Rename a file. Success is set True or False indicating if the rename is |
| -- successful or not. |
| -- |
| -- WARNING: In one very important respect, this function is significantly |
| -- non-portable. If New_Name already exists then on Unix systems, the call |
| -- deletes the existing file, and the call signals success. On Windows, the |
| -- call fails, without doing the rename operation. See also the procedure |
| -- Ada.Directories.Rename, which portably provides the windows semantics, |
| -- i.e. fails if the output file already exists. |
| |
| -- The following defines the mode for the Copy_File procedure below. Note |
| -- that "time stamps and other file attributes" in the descriptions below |
| -- refers to the creation and last modification times, and also the file |
| -- access (read/write/execute) status flags. |
| |
| procedure Set_Close_On_Exec |
| (FD : File_Descriptor; |
| Close_On_Exec : Boolean; |
| Status : out Boolean); |
| -- When Close_On_Exec is True, mark FD to be closed automatically when new |
| -- program is executed by the calling process (i.e. prevent FD from being |
| -- inherited by child processes). When Close_On_Exec is False, mark FD to |
| -- not be closed on exec (i.e. allow it to be inherited). Status is False |
| -- if the operation could not be performed. |
| |
| S_Owner : constant := 1; |
| S_Group : constant := 2; |
| S_Others : constant := 4; |
| -- Constants for use in Mode parameter to Set_Executable |
| |
| procedure Set_Executable (Name : String; Mode : Positive := S_Owner); |
| -- Change permissions on the file given by Name to make it executable |
| -- for its owner, group or others, according to the setting of Mode. |
| -- As indicated, the default if no Mode parameter is given is owner. |
| |
| procedure Set_File_Last_Modify_Time_Stamp (Name : String; Time : OS_Time); |
| -- Given the name of a file or directory, Name, set the last modification |
| -- time stamp. This function must be used for an unopened file. |
| |
| procedure Set_Non_Readable (Name : String); |
| -- Change permissions on the named file to make it non-readable for |
| -- its owner. The writable and executable permissions are not |
| -- modified. |
| |
| procedure Set_Non_Writable (Name : String); |
| -- Change permissions on the named file to make it non-writable for its |
| -- owner. The readable and executable permissions are not modified. |
| |
| procedure Set_Read_Only (Name : String) renames Set_Non_Writable; |
| -- This renaming is provided for backwards compatibility with previous |
| -- versions. The use of Set_Non_Writable is preferred (clearer name). |
| |
| procedure Set_Readable (Name : String); |
| -- Change permissions on the named file to make it readable for its |
| -- owner. |
| |
| procedure Set_Writable (Name : String); |
| -- Change permissions on the named file to make it writable for its owner |
| |
| function Write |
| (FD : File_Descriptor; |
| A : System.Address; |
| N : Integer) return Integer; |
| -- Write N bytes from address A to file referenced by FD. The returned |
| -- value is the number of bytes written, which can be less than N if a |
| -- disk full condition was detected. |
| |
| -- The following section contains low-level routines using addresses to |
| -- pass file name and executable name. In each routine the name must be |
| -- Nul-Terminated. For complete documentation refer to the equivalent |
| -- routine (using String in place of C_File_Name) defined above. |
| |
| subtype C_File_Name is System.Address; |
| -- This subtype is used to document that a parameter is the address of a |
| -- null-terminated string containing the name of a file. |
| |
| procedure Copy_File |
| (Name : C_File_Name; |
| Pathname : C_File_Name; |
| Success : out Boolean; |
| Mode : Copy_Mode := Copy; |
| Preserve : Attribute := Time_Stamps); |
| |
| procedure Copy_Time_Stamps |
| (Source : C_File_Name; |
| Dest : C_File_Name; |
| Success : out Boolean); |
| |
| function Create_File |
| (Name : C_File_Name; |
| Fmode : Mode) return File_Descriptor; |
| |
| function Create_New_File |
| (Name : C_File_Name; |
| Fmode : Mode) return File_Descriptor; |
| |
| procedure Delete_File (Name : C_File_Name; Success : out Boolean); |
| |
| function File_Time_Stamp (Name : C_File_Name) return OS_Time; |
| |
| function Is_Directory (Name : C_File_Name) return Boolean; |
| function Is_Executable_File (Name : C_File_Name) return Boolean; |
| function Is_Owner_Readable_File (Name : C_File_Name) return Boolean; |
| function Is_Regular_File (Name : C_File_Name) return Boolean; |
| function Is_Symbolic_Link (Name : C_File_Name) return Boolean; |
| function Is_Owner_Writable_File (Name : C_File_Name) return Boolean; |
| |
| function Locate_Regular_File |
| (File_Name : C_File_Name; |
| Path : C_File_Name) return String_Access; |
| |
| function Open_Append |
| (Name : C_File_Name; |
| Fmode : Mode) return File_Descriptor; |
| |
| function Open_Read |
| (Name : C_File_Name; |
| Fmode : Mode) return File_Descriptor; |
| |
| function Open_Read_Write |
| (Name : C_File_Name; |
| Fmode : Mode) return File_Descriptor; |
| |
| procedure Rename_File |
| (Old_Name : C_File_Name; |
| New_Name : C_File_Name; |
| Success : out Boolean); |
| |
| ------------------ |
| -- Subprocesses -- |
| ------------------ |
| |
| subtype Argument_List is String_List; |
| -- Type used for argument list in call to Spawn. The lower bound of the |
| -- array should be 1, and the length of the array indicates the number of |
| -- arguments. |
| |
| subtype Argument_List_Access is String_List_Access; |
| -- Type used to return Argument_List without dragging in secondary stack. |
| -- Note that there is a Free procedure declared for this subtype which |
| -- frees the array and all referenced strings. |
| |
| type Process_Id is private; |
| -- A private type used to identify a process activated by the following |
| -- non-blocking calls. The only meaningful operation on this type is a |
| -- comparison for equality. |
| |
| Invalid_Pid : constant Process_Id; |
| -- A special value used to indicate errors, as described below |
| |
| function Current_Process_Id return Process_Id; |
| -- Returns the current process id or Invalid_Pid if not supported by the |
| -- runtime. |
| |
| function Argument_String_To_List |
| (Arg_String : String) return Argument_List_Access; |
| -- Take a string that is a program and its arguments and parse it into an |
| -- Argument_List. Note that the result is allocated on the heap, and must |
| -- be freed by the programmer (when it is no longer needed) to avoid |
| -- memory leaks. |
| -- On Windows, backslashes are used as directory separators. On Unix, |
| -- however, they are used to escape the following character, so that for |
| -- instance "-d=name\ with\ space" is a single argument. In the result |
| -- list, the backslashes have been cleaned up when needed. The previous |
| -- example will thus result a single-element array, where the element is |
| -- "-d=name with space" (Unix) or "-d=name\ with\ space" (windows). |
| |
| procedure Kill (Pid : Process_Id; Hard_Kill : Boolean := True); |
| -- Kill the process designated by Pid. Does nothing if Pid is Invalid_Pid |
| -- or on platforms where it is not supported, such as VxWorks. Hard_Kill |
| -- is True by default, and when True the process is terminated immediately. |
| -- If Hard_Kill is False, then a signal SIGINT is sent to the process on |
| -- POSIX OS or a ctrl-C event on Windows, allowing the process a chance to |
| -- terminate properly using a corresponding handler. |
| |
| procedure Kill_Process_Tree (Pid : Process_Id; Hard_Kill : Boolean := True); |
| -- Kill the process designated by Pid and all it's children processes. |
| -- Does nothing if Pid is Invalid_Pid or on platforms where it is not |
| -- supported, such as VxWorks. Hard_Kill is True by default, and when True |
| -- the processes are terminated immediately. If Hard_Kill is False, then a |
| -- signal SIGINT is sent to the processes on POSIX OS or a ctrl-C event |
| -- on Windows, allowing the processes a chance to terminate properly |
| -- using a corresponding handler. |
| -- |
| -- Note that this routine is not atomic and is supported only on Linux |
| -- and Windows. On other OS it will only kill the process identified by |
| -- Pid. |
| |
| function Non_Blocking_Spawn |
| (Program_Name : String; |
| Args : Argument_List) return Process_Id; |
| -- This is a non blocking call. The Process_Id of the spawned process is |
| -- returned. Parameters are to be used as in Spawn. If Invalid_Pid is |
| -- returned the program could not be spawned. |
| -- |
| -- Spawning processes from tasking programs is not recommended. See |
| -- "NOTE: Spawn in tasking programs" below. |
| -- |
| -- This function will always return Invalid_Pid under VxWorks, since there |
| -- is no notion of executables under this OS. |
| |
| function Non_Blocking_Spawn |
| (Program_Name : String; |
| Args : Argument_List; |
| Output_File_Descriptor : File_Descriptor; |
| Err_To_Out : Boolean := True) return Process_Id; |
| -- Similar to the procedure above, but redirects the output to the file |
| -- designated by Output_File_Descriptor. If Err_To_Out is True, then the |
| -- Standard Error output is also redirected. Invalid_Pid is returned |
| -- if the program could not be spawned successfully. |
| -- |
| -- Spawning processes from tasking programs is not recommended. See |
| -- "NOTE: Spawn in tasking programs" below. |
| -- |
| -- This function will always return Invalid_Pid under VxWorks, since there |
| -- is no notion of executables under this OS. |
| |
| function Non_Blocking_Spawn |
| (Program_Name : String; |
| Args : Argument_List; |
| Output_File : String; |
| Err_To_Out : Boolean := True) return Process_Id; |
| -- Similar to the procedure above, but saves the output of the command to |
| -- a file with the name Output_File. |
| -- |
| -- Invalid_Pid is returned if the output file could not be created or if |
| -- the program could not be spawned successfully. |
| -- |
| -- Spawning processes from tasking programs is not recommended. See |
| -- "NOTE: Spawn in tasking programs" below. |
| -- |
| -- This function will always return Invalid_Pid under VxWorks, since there |
| -- is no notion of executables under this OS. |
| |
| function Non_Blocking_Spawn |
| (Program_Name : String; |
| Args : Argument_List; |
| Stdout_File : String; |
| Stderr_File : String) return Process_Id; |
| -- Similar to the procedure above, but saves the standard output of the |
| -- command to a file with the name Stdout_File and the standard output |
| -- of the command to a file with the name Stderr_File. |
| |
| procedure Normalize_Arguments (Args : in out Argument_List); |
| -- Normalize all arguments in the list. This ensure that the argument list |
| -- is compatible with the running OS and will works fine with Spawn and |
| -- Non_Blocking_Spawn for example. If Normalize_Arguments is called twice |
| -- on the same list it will do nothing the second time. Note that Spawn |
| -- and Non_Blocking_Spawn call Normalize_Arguments automatically, but |
| -- since there is a guarantee that a second call does nothing, this |
| -- internal call will have no effect if Normalize_Arguments is called |
| -- before calling Spawn. The call to Normalize_Arguments assumes that the |
| -- individual referenced arguments in Argument_List are on the heap, and |
| -- may free them and reallocate if they are modified. |
| |
| function Pid_To_Integer (Pid : Process_Id) return Integer; |
| -- Convert a process id to an Integer. Useful for writing hash functions |
| -- for type Process_Id or to compare two Process_Id (e.g. for sorting). |
| |
| procedure Spawn |
| (Program_Name : String; |
| Args : Argument_List; |
| Success : out Boolean); |
| -- This procedure spawns a program with a given list of arguments. The |
| -- first parameter of is the name of the executable. The second parameter |
| -- contains the arguments to be passed to this program. Success is False |
| -- if the named program could not be spawned or its execution completed |
| -- unsuccessfully. Note that the caller will be blocked until the |
| -- execution of the spawned program is complete. For maximum portability, |
| -- use a full path name for the Program_Name argument. On some systems |
| -- (notably Unix systems) a simple file name may also work (if the |
| -- executable can be located in the path). |
| -- |
| -- Spawning processes from tasking programs is not recommended. See |
| -- "NOTE: Spawn in tasking programs" below. |
| -- |
| -- Note: Arguments in Args that contain spaces and/or quotes such as |
| -- "--GCC=gcc -v" or "--GCC=""gcc -v""" are not portable across all |
| -- operating systems, and would not have the desired effect if they were |
| -- passed directly to the operating system. To avoid this problem, Spawn |
| -- makes an internal call to Normalize_Arguments, which ensures that such |
| -- arguments are modified in a manner that ensures that the desired effect |
| -- is obtained on all operating systems. The caller may call |
| -- Normalize_Arguments explicitly before the call (e.g. to print out the |
| -- exact form of arguments passed to the operating system). In this case |
| -- the guarantee a second call to Normalize_Arguments has no effect |
| -- ensures that the internal call will not affect the result. Note that |
| -- the implicit call to Normalize_Arguments may free and reallocate some |
| -- of the individual arguments. |
| -- |
| -- This function will always set Success to False under VxWorks and other |
| -- similar operating systems which have no notion of the concept of |
| -- dynamically executable file. Otherwise Success is set True if the exit |
| -- status of the spawned process is zero. |
| |
| function Spawn |
| (Program_Name : String; |
| Args : Argument_List) return Integer; |
| -- Similar to the above procedure, but returns the actual status returned |
| -- by the operating system, or -1 under VxWorks and any other similar |
| -- operating systems which have no notion of separately spawnable programs. |
| -- |
| -- Spawning processes from tasking programs is not recommended. See |
| -- "NOTE: Spawn in tasking programs" below. |
| |
| procedure Spawn |
| (Program_Name : String; |
| Args : Argument_List; |
| Output_File_Descriptor : File_Descriptor; |
| Return_Code : out Integer; |
| Err_To_Out : Boolean := True); |
| -- Similar to the procedure above, but redirects the output to the file |
| -- designated by Output_File_Descriptor. If Err_To_Out is True, then the |
| -- Standard Error output is also redirected. |
| -- Return_Code is set to the status code returned by the operating system |
| -- |
| -- Spawning processes from tasking programs is not recommended. See |
| -- "NOTE: Spawn in tasking programs" below. |
| |
| procedure Spawn |
| (Program_Name : String; |
| Args : Argument_List; |
| Output_File : String; |
| Success : out Boolean; |
| Return_Code : out Integer; |
| Err_To_Out : Boolean := True); |
| -- Similar to the procedure above, but saves the output of the command to |
| -- a file with the name Output_File. |
| -- |
| -- Success is set to True if the command is executed and its output |
| -- successfully written to the file. If Success is True, then Return_Code |
| -- will be set to the status code returned by the operating system. |
| -- Otherwise, Return_Code is undefined. |
| -- |
| -- Spawning processes from tasking programs is not recommended. See |
| -- "NOTE: Spawn in tasking programs" below. |
| |
| procedure Wait_Process (Pid : out Process_Id; Success : out Boolean); |
| -- Wait for the completion of any of the processes created by previous |
| -- calls to Non_Blocking_Spawn. The caller will be suspended until one of |
| -- these processes terminates (normally or abnormally). If any of these |
| -- subprocesses terminates prior to the call to Wait_Process (and has not |
| -- been returned by a previous call to Wait_Process), then the call to |
| -- Wait_Process is immediate. Pid identifies the process that has |
| -- terminated (matching the value returned from Non_Blocking_Spawn). |
| -- Success is set to True if this sub-process terminated successfully. If |
| -- Pid = Invalid_Pid, there were no subprocesses left to wait on. |
| -- |
| -- This function will always set success to False under VxWorks, since |
| -- there is no notion of executables under this OS. |
| |
| procedure Non_Blocking_Wait_Process |
| (Pid : out Process_Id; Success : out Boolean); |
| -- Same as Wait_Process, except if there are no completed child processes, |
| -- return immediately without blocking, and return Invalid_Pid in Pid. |
| -- Not supported on all platforms; Success = False if not supported. |
| |
| ------------------------------------- |
| -- NOTE: Spawn in Tasking Programs -- |
| ------------------------------------- |
| |
| -- Spawning processes in tasking programs using the above Spawn and |
| -- Non_Blocking_Spawn subprograms is not recommended, because there are |
| -- subtle interactions between creating a process and signals/locks that |
| -- can cause trouble. These issues are not specific to Ada; they depend |
| -- primarily on the operating system. |
| |
| -- If you need to spawn processes in a tasking program, you will need to |
| -- understand the semantics of your operating system, and you are likely to |
| -- write non-portable code, because operating systems differ in this area. |
| |
| -- The Spawn and Non_Blocking_Spawn subprograms call the following |
| -- operating system functions: |
| |
| -- On Windows: spawnvp (blocking) or CreateProcess (non-blocking) |
| |
| -- On Solaris: fork1, followed in the child process by execv |
| |
| -- On other Unix-like systems: fork, followed in the child |
| -- process by execv. |
| |
| -- On vxworks, spawning of processes is not supported |
| |
| -- For details, look at the functions __gnat_portable_spawn and |
| -- __gnat_portable_no_block_spawn in adaint.c. |
| |
| -- You should read the operating-system-specific documentation for the |
| -- above functions, paying special attention to subtle interactions with |
| -- threading, signals, locks, and file descriptors. Most of the issues are |
| -- related to the fact that on Unix, there is a window of time between fork |
| -- and execv; Windows does not have this problem, because spawning is done |
| -- in a single operation. |
| |
| -- On Posix-compliant systems, such as Linux, fork duplicates just the |
| -- calling thread. (On Solaris, fork1 is the Posix-compliant version of |
| -- fork.) |
| |
| -- You should avoid using signals while spawning. This includes signals |
| -- used internally by the Ada run-time system, such as timer signals used |
| -- to implement delay statements. |
| |
| -- It is best to spawn any subprocesses very early, before the parent |
| -- process creates tasks, locks, or installs signal handlers. Certainly |
| -- avoid doing simultaneous spawns from multiple threads of the same |
| -- process. |
| |
| -- There is no problem spawning a subprocess that uses tasking: the |
| -- problems are caused only by tasking in the parent. |
| |
| -- If the parent is using tasking, and needs to spawn subprocesses at |
| -- arbitrary times, one technique is for the parent to spawn (very early) |
| -- a particular spawn-manager subprocess whose job is to spawn other |
| -- processes. The spawn-manager must avoid tasking. The parent sends |
| -- messages to the spawn-manager requesting it to spawn processes, using |
| -- whatever inter-process communication mechanism you like, such as |
| -- sockets. |
| |
| -- In short, mixing spawning of subprocesses with tasking is a tricky |
| -- business, and should be avoided if possible, but if it is necessary, |
| -- the above guidelines should be followed, and you should beware of |
| -- portability problems. |
| |
| ------------------- |
| -- Miscellaneous -- |
| ------------------- |
| |
| function Errno return Integer; |
| pragma Import (C, Errno, "__get_errno"); |
| -- Return the task-safe last error number |
| |
| function Errno_Message |
| (Err : Integer := Errno; |
| Default : String := "") return String; |
| -- Return a message describing the given Errno value. If none is provided |
| -- by the system, return Default if not empty, else return a generic |
| -- message indicating the numeric errno value. |
| |
| function Getenv (Name : String) return String_Access; |
| -- Get the value of the environment variable. Returns an access to the |
| -- empty string if the environment variable does not exist or has an |
| -- explicit null value (in some operating systems these are distinct |
| -- cases, in others they are not; this interface abstracts away that |
| -- difference. The argument is allocated on the heap (even in the null |
| -- case), and needs to be freed explicitly when no longer needed to avoid |
| -- memory leaks. |
| |
| procedure OS_Abort; |
| pragma Import (C, OS_Abort, "abort"); |
| pragma No_Return (OS_Abort); |
| -- Exit to OS signalling an abort (traceback or other appropriate |
| -- diagnostic information should be given if possible, or entry made to |
| -- the debugger if that is possible). |
| |
| procedure OS_Exit (Status : Integer); |
| pragma No_Return (OS_Exit); |
| -- Exit to OS with given status code (program is terminated). Note that |
| -- this is abrupt termination. All tasks are immediately terminated. There |
| -- are no finalization or other Ada-specific cleanup actions performed. On |
| -- systems with atexit handlers (such as Unix and Windows), atexit handlers |
| -- are called. |
| |
| type OS_Exit_Subprogram is access procedure (Status : Integer); |
| |
| procedure OS_Exit_Default (Status : Integer); |
| pragma No_Return (OS_Exit_Default); |
| -- Default implementation of procedure OS_Exit |
| |
| OS_Exit_Ptr : OS_Exit_Subprogram := OS_Exit_Default'Access; |
| -- OS_Exit is implemented through this access value. It it then possible to |
| -- change the implementation of OS_Exit by redirecting OS_Exit_Ptr to an |
| -- other implementation. |
| |
| procedure Set_Errno (Errno : Integer); |
| pragma Import (C, Set_Errno, "__set_errno"); |
| -- Set the task-safe error number |
| |
| procedure Setenv (Name : String; Value : String); |
| -- Set the value of the environment variable Name to Value. This call |
| -- modifies the current environment, but does not modify the parent |
| -- process environment. After a call to Setenv, Getenv (Name) will always |
| -- return a String_Access referencing the same String as Value. This is |
| -- true also for the null string case (the actual effect may be to either |
| -- set an explicit null as the value, or to remove the entry, this is |
| -- operating system dependent). Note that any following calls to Spawn |
| -- will pass an environment to the spawned process that includes the |
| -- changes made by Setenv calls. |
| |
| Directory_Separator : constant Character; |
| -- The character that is used to separate parts of a pathname |
| |
| Path_Separator : constant Character; |
| -- The character to separate paths in an environment variable value |
| |
| private |
| pragma Import (C, Path_Separator, "__gnat_path_separator"); |
| pragma Import (C, Directory_Separator, "__gnat_dir_separator"); |
| pragma Import (C, Current_Time, "__gnat_current_time"); |
| pragma Import (C, Current_Process_Id, "__gnat_current_process_id"); |
| |
| type OS_Time is |
| range -(2 ** 63) .. +(2 ** 63 - 1); |
| -- Type used for timestamps in the compiler. This type is used to hold |
| -- time stamps, but may have a different representation than C's time_t. |
| -- This type needs to match the declaration of OS_Time in adaint.h. |
| |
| Invalid_Time : constant OS_Time := -1; |
| -- This value should match the return value from __gnat_file_time_* |
| |
| pragma Import (Intrinsic, "<"); |
| pragma Import (Intrinsic, ">"); |
| pragma Import (Intrinsic, "<="); |
| pragma Import (Intrinsic, ">="); |
| pragma Inline (To_C); |
| pragma Inline (To_Ada); |
| |
| type Process_Id is new Integer; |
| Invalid_Pid : constant Process_Id := -1; |
| |
| end System.OS_Lib; |